Beneficiation of poor Grade Kyanite from Amda Lapso Mines, Bihar

A sample of poor grade kyanite from Amda Lapso kyanite mines was received from M/S Indian Copper Corporation, Ghatsila, Bihar for beneficiation tests. The sample as received assayed 38.2% Al203, 50.6%Sio2,3.1% Fe2O3,1.0%TiO2,2.4%CaO,1.5%MgO,i.15%(Na2O+K2O).Quartz and muscovite were the main gangue minerals with minor quantities of Sericite, Chlorite, Rutile, etc. Hydroclassification followed by Tabling at -48 mesh did not give satisfactory results. Flotation with a deslimed feed at 3.8 pH employing Lactic acid and sodium sulphonate followed by four cleanings yielded a final concentrate assaying 60.4% Al2O3, with a recovery of 48.8% Kyanite in it.